Describe multimedia database and what are the different types of multimedia data that are available in current systems?

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 Multimedia database (MMDB)

 A Multimedia database (MMDB) is a collection of related multimedia data. The multimedia data include one or more primary media data types such as text, images, graphic objects (including drawings, sketches, and illustrations) animation sequences, audio, and video.

There is a number of data types that can be characterized as multimedia data types. These are typically the elements or the building blocks of ore generalized multimedia environments, platforms, or integrating tools. The basic types can be described as follows :

1. Text: The form in which the text can be stored can vary greatly. In addition to ASCII-based files, the text is typically stored in processor files, spreadsheets, databases, and annotations on more general multimedia objects. With the availability and proliferation of GUIs and text fonts the job of storing text is becoming complex allowing special effects(color, shades..).

2. Images: There is great variance in the quality and size of storage for still images. Digitalized images are a sequence of pixels that represents a region in the user's graphical display. The space overhead for still images varies on the basis of resolution, size, complexity, and compression scheme used to store images. The popular image formats are jpg, png, BMP, and tiff.

3. Audio: An increasingly popular datatype being integrated with most of the applications is Audio. It's quite a space intensive. One minute of sound can take up to 2-3 Mbs of space. Several techniques are used to compress it into a suitable format.

4. Video: One of the most space-consuming multimedia data types is digitalized video. The digitalized videos are stored as a sequence of frames. Depending upon its resolution and size a single frame can consume up to 1 MB. Also to have realistic video playback, the transmission, compression, and decompression of digitalized require a continuous transfer rate.

5. Graphic Objects: These consists of special data structures used to define 2D & 3D shapes through which we can define multimedia objects. These include various formats used by image and video editing applications.



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